albbechf



i A.' w.' ALBRECHT. yPROCESS 0F MANUFACTURING PISTON RINGS. u APPLICATION FILED APR. 9.1918.

Patented Sept. 9, 1919.

asia/lait rimosse orinnivuracruniiio memoir-ritueel To all whom it may concern.'

Be it known that ll, ALBERT Ailiiniiorrr.,

a citizen of thev United States, residing at the city of St. Louis and State of Missouri, have invented a new and useful Process of Manufacturing Piston-Rings, of which the following is a specification. l

rlhis invention rel( tes to the art of manuu facturing piston rings. 4

in object of the invention is to provide a new and improved process of forming 'a piston ringI by subjecting a baute pressure by which the bar is formed into rino having overlapping portions connected y an integral bent portion and by which the overlapping portions are caused to press against each other by the resiliency of the material.

Other objects will appear from the following description, reference being made the drawing, in which- Figure l is a broken view of the bar from which the piston ring is made.

Fig. ilEL is a view illustrating the bar odset prior to being rolledinto the form of a ring.

Fig. 2 vis a view looking toward the periphery of the finished ring.

Fig. 3 is a side elevation of the finished rin lgii Fig. l is illustrated a bar which in its finished form is preferably one-half the width of the finished ring. The b'ar illustrated is subjected to pressure by which it is rolled to form a ring having overlapping portions extending preferably nearly the entire circumference of the ringNAt the same time that the bar is being rolled into the form of a ring it is subjected to lateral pressure midway between its ends in opposite directions so that a bent portionl is formed, thus odsetting one coil or helix of the ring from the other coil or helix and forming the ring so that the two opposite side 'edges are parallel with each other throughout and are' at all points at right angles to the axis of the ring. The bend l is preferably `oblique, as shown in Fig. 2, so that the circumferential length of the bar when formed into the finished ring is only slightly less than' the extended length of the bar before the ring'is formed.

The bar is coiled into a ring of a diameter slightly larger than the diameter of the cylinder for which it is intended, so that the ring may be compressed into the cylinder, and to permit such compression the ends 2 are spaced from the bent connecting miur-umm Stpeciiicatlon of Letters Patent.

Patented sept.. u, .'l

amusante niet time e, ieia semi no. sentir.

portion 1 thus leaving room for the moveinentof the end portions when being compressed into the cylinder.

subiectng the bar to proper pressure win e being coiled into the ring nofinishing 'treatment is necessary since the pres.- sure will produce the desired smooth surfaces on the ring and will prevent any portion of the ring or bar from being excessively strained in the course of manufacture. However, if preferred, the ring may be ground or finished after being formed, and I do not restrict myself to a procedure in which the surfaces are nislied by pressure., By the use of pressure in the course of manufacture the overlapping portions of the ring are caused to press closely against to-"""each other inthe finished ring and this resuit is eected without resort to treatment after the bar has beencoiled into annular forrn.

lt will be understood, of course, that the odset 1 may be formed before the bar. is coiled int-o the annular form, or that the oifset may be formed concurrently with the formation of theannulus.l ln this particular l do not confine myself to any specific order of procedure, though it is preferred that the offset bend be formed concurrently with the formation of the ring.

I claim:

l. The process of forming a piston ring having overlapping portions, which. consists in rol i a ring having overlap-ping portions and simultaneously bending; thebarso that. the overlapping portions press against each other sidewise.

2. The process of forming a piston ring, which consists in bending a bar so that one 'edge of one portion thereof is in alinernent with the opposite edge of the other portion thereof, .and simultaneously rolling the bar to provide overlapping portions.

3. rlllie process of forming a piston rind having overlapping end portions, whic ng air elongated bar intolthe form of lcomprises bending a long bar obliquely toi aiinnu'r vv. niinnnoii'r. 

